javascript - "this" within setTimeout self executing function is undefined -

i know within settimeout correspond default window, have been using bind , passing through self executing function, when settimeout runs (it's fine on first run, called teabot._managetearound(), it's not fine when self executing) undefined. here's code, going wrong? (i have deleted lines of code might not relevant). :)

teabot.prototype._managetearound = function(originalmessage, channel){     var self = this;     self.teamaker = this._getuserbyid(originalmessage.user);      //now wait 3 minutes people send order     self._runtimer(self,channel); } teabot.prototype._runtimer =function(self, channel) {     // stuff     console.log(self.teamaker.name); //undefined      var interval = self.interval,         teamaker = self.teamaker;      console.log("self.interval " + self.interval);      if(interval === 0){          interval++;         self.interval = interval;          settimeout(self._runtimer.bind(self, channel), 180000);      }else{         self.interval = 0;     } } 

this line problematic:

settimeout(self._runtimer.bind(self, channel), 180000); 

function teabot.prototype._runtimer expects self first param - function.prototype.bind() first param context (function's this). try use this:

settimeout(self._runtimer.bind(self, self, channel), 180000); 

or leave context empty, becouse not using this @ all:

settimeout(self._runtimer.bind(undefined, self, channel), 180000);